Electric signaling system.



PATENTED SEPT. 6, 1904.

APPLICATION FILED NOV. 30, 1903.

2 SHEETS-SIIEET 1- N0 MODEL.

PATENTED SEPT. 6, 1904 P. H. SOHMITT.

ELECTRIC SIGNALING SYSTEM.

APPLICATION FILED NOV 30, 1903.

2 SHEETSSHEET 2.

NO MODEL,

UNITED STATES Patented September 6, 190

PATENT ()EEicE.

ELECTRIC SIGNALING SYSTEM.

SPECIFICATION forming part of Letters Patent No. 769, iO9,

dated September 6, 1904.

Application filed November 30, 1903. Serial No. 183,092. (No model.)

Be it known that 1, PAUL II. Sornn'r'r, of Uhicago. in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Electric Signaling Systems; and I do hereby declare that the following is a full, clear, and exact description thereof. reference being had to the accompanying drawings. and to the letters of reference marked thereon, which form a part of this sptcitication.

This invention relates to an electric signaling system, such as is used in transmitting lire-alarm signals and for like purposes, of that class which is adapted to operate either as a closed and open circuitsystem or one in which the parts are so arranged that signals are in the normal operation of the system transmitted through a closed circuit, but in case of a break in such closed circuit the system will continue to operate with an open circuit.

My invention may be more readily understood by reference to the accompanying drawings. in which-- Figure l is a diagrammatic view showing the apparatus at a main or central station and a signal-transmitting station with connecting lines or wires made in accordance with my invention. Fig.2 is a diagrammatic side view showing the wires at one of the signal-stations. Fig. 3 a view in front elevation of the apparatus in one of the signal-boxes. Fig. A is a sectional view thereof, taken upon line A 4: of Fig. 3. Fig. 5 is a detail plan section taken upon line 5 5 of Fig. 3. Fig. 6 is a detail section taken upon line 6 6 of Fig. 3.

The apparatus at the central station embraces a main battery A, a relay B, a local battery (I, a recording device I), and a threebladed switch E.

F indicates the main line-wire, which extends from the center station to and also between the several signal-stations or alarmboXes, which are indicated by G G G: Said wire F constitutes the conductor of a closed or loop circuit. The drawings illustrate three alarm-boxes in the loop-circuit, but show only one of them, (i, in detail.

The three blades 0 c c of the switch E are pivoted to posts H H II and are adapted for engagement with two sets of contact-pieces I .l I and J J J. The three blades of the said switch are shown as engaged with the contact-pieces I I, I and free from contact with the contact-pieces J J J.

Referring to the electric connections at the central station, a wire 11 leads from the main battery A to the center post II of the said switch and a wire (1 leads from the said battery to the magnet-coils of the relay B. The relay B has an armature B, which swings between and is adapted for contact with two contact-points 1). \Vhen the relay-magnet energized, the armature rests against or makes contact with the point 6; but when no current is passing through the magnet-coils said armature is held by its retracting-spring against the point 7). A wire 11 leads from said magnet-coils to the post II of the switch, while a wire 1' connects the contact-point I with a post J, which post is adapted for contact with the middle blade a of the switch when the said middle blade is engaged with the contactpiece J. A wire leads from the contactpiece I to the contact-piece J. One terminal of the main circuit-wire F is connected with the wire a between the contact-pieces I J, while the other terminal of said main wire F is connected with the contact-piece I. From the above it will be understood that when the switch is in the position illustrated, which is its normal position, the main linecircuit may be traced from the main battery A through the wire a, the switch-post H, the switch-blade w, the contact-piece I, the wire a", the main line-wire F, the contact-piece I, the blade r of the switch, the pivot-post H, the wire a the coils of the relay, and wire a, back to the main battery A. l

A wire j leads from the contact-point J to the ground and constitutes a ground connection for the main line when the switch is reversed or has its blades engaged with the contact-pieces .I, J, and J \Vhen the switch is so reversed, the main line-circuitmay be traced from the ground through the wire j to the contact-piece J, the switch-bhule w, the post H, the wire a, the coils of the relay, the wire a, the main battery, the wire (1, an I the middle blade 0 of the switch, the contact-piece J the wire 71, and the main line conductor F. At this time likewise a circuit may be traced from the ground through the wire j, contactpiece J, the blade 6 of the switch, the pivotpost H, the wire a the coils of the relay, the wire a, the main battery, the wire a, the pivot-post H, the central blade 6 of the switch, the contact-piece J, and the wire 71 to the opposite terminal of the main line conductor F.

The local circuit at the main station embraces a wire 0, leading from the local battery 0 to the recording device D, a wire d, leading from said recording device to the pivot-post H of the switch E, a wire 0', leading from the said local battery to the armature B of the relay B, a wire 0 leading from one contact-point Z) of said relay to the contactpiece J and a wire 0 leading from the other contact-point b of said relay to the contact-piece 1 The local circuit thus embraces two branches, one through the wire 0 and the other through the wire 0". In the normal operation of the posts or when the loop-circuit is closed the branch through the wire 0 will be broken at the switch E and will be out of use, and the contact-point 5 will act merely as a stop for the armature, which when released by the breaking of the loop-circuit will make contact with the point I), and thereby close the local circuit through the branch 0 and the recording device. \Vhen, however, the loop-circuit is broken and the system is operating as an opencircuit system, the armature B will be held against the point 6, the wire 0 will be out of use, and as the switch-blade 0 will connect the post H with the contact-piece J the wire 0 will form'part of the local circuit, so that when the relay-magnet is energized its armature will be brought against the point 5 and the local circuit will be closed through the wire 0 In the ordinary operation of the apparatus and when the switch E is in the position shown with its blades in contact with the contactpieces I, I, and I the local circuit. by which the recording apparatus D is operated, may be traced as follows: from the local battery C through the wire 0, the recorder D, the wire (Z, the post H of the switch, the blade of the switch, the contact-piece 1 the wire 0 the point 5 of the relay B, and the wire 0, back to the local battery C. As the armature of the relay is released through the breaking of the main circuit, said armature makes contact with the contactpoint 5 of said relay, thereby closing the circuit above described and operating the recording device. When, however, the switch E is reversed from the position shown and the main-line circuit works as an open circuit through the ground-line j, then the local circuit may be traced from the local battery C through the wire 0, the recorder D, the wire (Z, the pivot-post H the contact-piece J the wire 0 the contact-point b of the relay,

and the wire 0, back to the local battery. hen the main line is working in open circuit, the lever of the relay will be held in contact with the contact-point & of the relay and when the circuit is closed said lever will be drawn against the point 5, thus closing the circuit last described and operating the recording device D. The devices at one of the alarm-boxes or signal-stations are shown diagrammatically in Figs. 1 and 2 and in detail in Figs. 3 to 6. These devices embrace features as follows: K and L are two signal-transmitting wheels or disks which are rigidly connected and turn with each other, but are electrically separated or insulated from each other by means of an insulating-sleeve Z. Said disks are attached to the shaft M of a spring-motor consisting of a train of gears and a coiled actuating-spring N. This spring is mounted on a shaft N, provided at its outer end with a crank-arm N which may be turned or moved against the action of the spring N to tighten or wind the same. Said shaft N carries a spur-wheel N", which is connected with the shaft by a pawland-ratchet connection constructed to permit the spring N to be placed under tension by the turning of the shaft without turning of the said spur-wheel i but adapted to transmit motion from the shaft of the spur-Wheel when the said shaft is turned by the action of said spring. Said spur-wheel N 3 is connected with the shaft M by intermediate gearing, and such gearing embraces an escape-wheel N, which operates upon a pallet which is attached to a weighted oscillatory arm N by which the speed of rotation of the train of gears and the disks K and L under the action of the spring N is controlled. 0 is a contact-arm which is adapted for engagement with one or the other of the disks K or L, said disks being separated by a space into which the said contact-arm extends and the contact-arm being movable to bring it into contact with either of said disks. The disk K is a circuit-breaking disk and is provided with a series of notches, while the disk L is a circuit-closing disk and provided with a series of teeth or projections, the notches and teeth on the two disks being arranged on adjacent faces of the disks, so that the end of the contact-arm 0 may be brought into position to engage the working faces of either disk by the movement or shifting of said arm toward one or the other of said disks. Said contact-arm is attached to and moved by the armature P of an electromagnet Q, the coils of which are connected with the loopcircuit and energized by the current through the same. The armature P is pivoted by a horizontal pivot 19 to a bracket R, attached to the rear wall of the box R. Attached to the said armature is a rigid arm P carrying at its free end a bell-hammer p. Said bell-hammer is adapted to strike a bell R attached, preferably, to the bottom of the box R. A

coiled contractile spring P is connected with the arm P and with the rear wall of the box, said spring acting to draw the arm P inwardly and to retract the armature from the magnet Q. Said spring P is so adjusted that it will yield to permit the armature to approach the magnet Q when the main-line current passes through the coils of said magnet. Moreover, the bell-hammer will strike the bell each time the armature is actuated by the magnet. The contact-arm O is insulated from the armature P by an insulating-strip P. The pivot p of the armature is so arranged with respect to the disks K and L that when the upper end of the armature swings toward the magnet Q the upper end of the contact-arm 0 will be carried into contact with the circuit-incaking disk K, and when said armature is retracted said arm will be brought against the circuitclosing disk L. The said arm 0 is divided at its upper end into two prongs, one of which is bent inwardly and is adapted for contact with the notched face of the disk K, while the other is bent outwardly and is adapted for contact with the teeth of the disk L. \Vhen the armature P is held at the inward limit of its movement or adjacent to the magnet Q by the attractive action of the latter. the arm 0 will be in position for contact with the disk K, and when the said armature is drawn away from the magnet by the spring P the said arm 0 will be in position for contact with the teeth on the disk L. Attached to the outer face of the arm 0 is a spring contact-arm O, which is adapted for contact when the armature is retracted with a contact-screw r, which is mounted on an arm 1", attached to a post R on the rear wall of the box, said screw r being in metallic connection with the box. Said contact-arm O and the contact-screw 1' constitute a switch which when closed by the retraction of the armature brings the contactarm 0 into electrical connection with the loopcircuit A at one side of the alar1n-l )ox. Said contact-arm is constantly in electric connection with the loop-circuit at the other side of said box through the coils of the electromagnet Q. Attached to the armature P is a laterally-extending locking-arm P, having fiat sides which are parallel with the armature. S indicates a swinging locking-sector which is adapted to coact with the arm P to hold the armature positively either in its inward or in the retracted position. Said sector is pivotally mounted on a post s, Fig. 6, so that it will swing in a plane parallel with the arm P, and the sector is adapted for contact either with the front or rear surface of the arm P, according to the position of the armature. The locking-sectorShasattachcd to it an arm S, which extends horizontally therefrom and which is connected at its free end by a pitman s with an arm S on the rock-shaft N. Below the arm S is a contact-plate T, which 1 above and free from said locking-arm P.

Said plate T is so located that the arm S will be in contact therewith when the sector is swung upwardly and its lower end stands above and free from the arm P of the armature, the parts being held in this position by the action of the train-actuating spring N, which tends to turn the shaft N in a direction to depress the arm S and to hold the arm S against the contactplate T and the sector S It follows from this construction that when the crank N is turned the sector S will be carried into contact with the outer face of the arm P if the armature be drawn inwardly and will come in contact with the outer face of the said arm if the armature be retracted and in either case will hold or lock the armature from movement dn ring the backward movement of the sector under the action of the train-actuating spring N and until the parts driven by the train of gears have completed their movement and the arm S strikes the plate T. U indicates a brush which bears on the outer or smooth face of the disk L and which is supported from the rear wall of the body by a post U, from which said brush is insulated by an insulating-block M.

The arrangement of conductors employed in connection with the parts described is more plainly indicated in Figs. land 2, from which it will be seen that one terminal, 7", of the main line-wire F is connected with the metal wall of the box, while the opposite terminal,

7" of said main line leads to the magnet (l. 3 \z A wire r leads from the said magnet Q to the contactplate T, and a wire z connects said contactplate T with the contact-arm O. The arm S of the locking-sector is in metallic connection with the metal wall of the box, so that when the said arm in contact with the plate T an electric connection is maintained between the coils of the magnet Q, and the terminal f of the loop-circuit through the wire 1 plate T. and said arm S. The plate T and arm S therefore constitute a switch which is operated by the movements of the locking device or the motor and by which the main line-circuit when the switch is closed is directed away from the contact-arm O and disk K and passes from the magnet-coils directly to the terminalf. A wire u loads from the brush U to the ground. The screw 1', arm 1', and post it constitute, as shown in Fig. 2, a conductor by which when the armature is retracted and the arm 0 is in position to coact with the circuit-closing disk L said arm 0 is brought into electric connection with the wall of the box and through the same with the tcrminalfof the main line-wire, said arm 0 at this time being also in electrical connection with the other terminal, f". through the magnet-coils and wires 1 and z. The circuit-closing disk L being constantly connected with the ground by the brush U is insulated from the box by insulation T. and wire 1!, it follows that when the switch formed by the contact-arm O and screw 9" is closed, which occurs when the loop-circuit is broken and the armature is retracted, the main-battery circuit may be closed by the contact of the contact-arm with the projections of the disk L either through the ground, the terminal f, and one side of the loop-circuit to the main battery at central station or through the ground, the terminal f, and the other side of the loop-circuit to the main battery, signals being transmitted through one side or the other of the loop-circuit, according to the location of the break in the latter.

Now referring to the operation of the devices contained in the alarm-box, as described, the parts are shown in their usual positions or when the main line is working with a closed circuit. At this time the current from the main battery will pass through the magnet Q and hold the armature P in contact therewith, While keeping the contact-arm O in position to act on the notched or circuit-breaking disk K. The circuit may then be traced from the main-line terminal f through the coils of the magnet Q, the wire q, the contact-plate T, the arm S, and the walls of the box to the main line terminal f. If the box be now pulled to send in an alarm, the movement of the crank N will shift the sector S into its locking position, so that it will hold the armature against the magnet and the arm 0 against the disk K and at the same time carry the arm S of the sector away from the contact-plate T. The working circuit may then be traced from the terminal f through the magnet-coils, the wires q and t, the contactarm 0, the disk K, and the walls of the box to the terminal f. After the crank is released the disk K will be turned by the spring N until it makes a complete rotation, and as it turns the circuit will be interrupted whenever one of the notches in the disk passes beneath the contact end of the arm 0. The desired signal will thus be sent to the central station and there indicated on the recorder and by an alarm-bell, if desired. As soon as the spring N has returned the parts to their usual position the arm S will again make contact with the plate T, and the circuit will be completed through said plate and arm as before.

If there be a break in the main line, then the magnet Q will no longer attract the armature P and the latter will fall back so as to bring the spring contact-arm 0 into contact with the screw 7* and to also carry the arm 0 away from the disk K and into position to be struck by the teeth on the disk L. If now the box-be pulled, the sector S will be carried behind the armature-arm p, so as to lock the said armature in its retracted position, while the arm S will be carried away from the contact-plate T. The parts will then be in condition for transmission of the signals through the unbroken side of the main circuit and the ground by closing of the open circuit thus formed; but to enable this to be done the switch E at the main station will first have to be reversed, as will hereinafter appear.

The operation of the parts in the box in transmitting by open circuit will be as follows: When the disk L is turned by the spring N upon the release of the crank N as soon as one of the teeth on said disk makes contact with the arm 0 a circuit will be closed from one of the main-line terminals f or f (according to the side of the box at which the break has occurred,) as follows: from the terminal f through the box-wall, the post R the arm a", the screw 7'', the contact-arm O, the arm 0, the disk L, the brush U, and wire a to the ground, or from the terminal f through the magnet-coils, the wires 9 and 2/, the arm 0, the disk L, the brush U, and wire a to the ground.

Now referring to the operation of the parts at the main station in case of a break inthe main line between boxes or between the main station and the box at either side thereof as soon as the main line-circuit is broken the lever B of the relay B is released and falls back against the contact-point b. As soon as this occurs (which may be indicated by an alarmbell, which is not necessary to illustrate) the operator reverses the switch E, and thereby connects both sides of the main line with the main battery A and the latter with the ground. When the switch is reversed from the position shown in Fig. 1, then the main battery A will be connected with the ground through the wire a, the coils of the relay B, the wire a the pivot-post H, the contact-piece J, and the wire At the same time the opposite pole of the battery will be connected with both sides or terminals of the broken main circuit, in one instance through the wire a, post H, contact-piece J and wire a to wire F, and in the other instance through the wire a, pivotpost H, contact-piece J, and wire 2" to wire F. Signals may now be sent from a box connected with either side of the main line-circuit, the closing of the open circuit at the box resulting in the armature B of the relay'B being drawn away from the contact-pointb and against the contact-point 6, with the result of closing the local circuit from the local battery O through the wire 0, armature B, wire 0 contact-piece J pivot-post H wire (Z, recorder D, and wire 0 to the local battery. Signals may be thus transmitted from the main circuit to the local circuit when said circuit is operating as an open circuit in the same manner as when the main circuit is working normally or as a closed circuit.

I claim as my invention 1. A signaling system embracinga normally closed loop-circuit, a main-station apparatus including a main battery and a switch through which the opposite poles of the battery are normally connected with the terminals of said loop-circuit but which, when reversed, connects one pole of said battery with the ground and the other pole of said battery with both terminals of the said loop-circuit, and a signaling-station embracing a circuit-breaking means, circuit-closing means, and a switch operated by an eleetromagnet in the loopcircuit, said switch, when in its usual position, maintaining the circuit-breaking devices in operation and when released operating to bring the circuit-closingdevice into operation.

2. A signaling system embracing-a normally closed loop-circuit, and a signaltransmitting device in said circuit embracingcircuit-breaking means, circuit-closing means, and an electromagnet in the loop-circuit adapted to maintain the circuit-breaking devices in position for operation when the loop-circuit is closed and to bring the circuit-closing means into condition for operation when the loopcireuit is open.

3. A signal-transmitting device comprising rotative circuit-breaking anthcircuit-closing disks which are insulated from each other, a movable contact-arm located between and adapted for engagement with either of said disks, and an electromagnet applied to move said contact-arm.

A. A signal-transmitting device comprising rotative circuit-breaking and circuit-closing disks which are insulated from each other, a movable contact-arm adapted to coact with either of said disks, an electromagnet applied to move said arm and a spring-motor which turns said disks.

5. A signail-transmitting device comprising rotative circuit-breaking and circuit-closing disks which are insulated from each other. a movable contact-arm adapted to coact with either of said disks, an electroniagnet applied to move said arm, a switch controlled by the electromagnet which operates when the loopcircuit is broken to bring the contact-arm and the circuit-closing disk in electrical connection with the signaling-circuit and with the ground.

6. A signal-transmitting device comprising rotative circuit-breaking and circuit-closing disks which are insulated from each other, a spring-motor which turns said disks, a con 'tact-arm adapted to coact with either of said disks, an eleetromagnet applied to move said arm, and a switch which is operated by the motor and which, when closed, diverts the signaling-circuit from the contact-arm and circuit-breaking disk.

7. A signal-transmitting device comprising rotative circuit-breaking and circuit-closing disks, which are insulated from each other, a movable contact-arm adapted to coact with either of said disks, an electromagnet applied to move said arm and a locking device adapted to positively hold the said contact-arm in position to coact with one or the other of said disks.

8. A signal-transmitting device comprising rotative circuit-breaking and circuit-closing disks which are insulated from each other, a contact arm adapted for engagement with either of said disks, anelectromagnet applied to move said arm into contact with one or the other of said disks, and a brush which acts on the circuit-closing disk and connected with the ground.

9. A signal-transmitting device embracing rotative circuit breaking and closing disks which are insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet the armature of which is connected with and gives movement to said arm, a spring-actuated motor for turning said disks, and a locking device operated by the motor for holding the said arm in either one of its two positions during the turning of the disks.

1.0. A signal-transmi tting device embracing rotative circuit breaking and closing disks which are electrically insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet the armature of which is connected with said contact-arm, said armature being adapted, when the magnet energized, to hold the contactarm in position to coact with the circuit-breaking disk, and when the magnet is inactive and the armature retracted to hold the contactarm in position to coact with the circuit-closing disk.

11. A signal-transmitting device embracing rotative circuit breaking and closing disks which are insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet the armature of which is connected with and gives movement to said arm, a spring-actuated motor for turning said disks, and a locking device embracing a locking-arm on the armature and a movable locking-segment adapted to engage one side or the other of said locking-arm to hold the contact-arm in either one of its two positions, said lockingsegment being connected with and operated by said motor.

12. A signal-transmitting device embracing rotative cireuit-ln'eaking and circuit-closing disks which are electrically insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet the armature of which is connected with and gives movement to said arm, said armature being adapted, when the magnet is energized, to hold the contact-arm in position to coact with the circuit-lneaking disk, and when the magnet is inactive and the armature is retracted to hold the contact-arm in position to coact with said circuit-closing disk, a spring-motor by which the said disks are turned, a locking device constructed to hold said contact-arm in one or the other of its two positions, said locking device embracing a locking element which is normally disengaged from its coacting element, and a switch one member of which is in electrical connection with the coils of said electromagnet and the other member of which is connected and moves with said locking member, said switch being closed, when the locking member is in its disengaged position, to divert the signaling-circuit from the said contact-arm and circuit-breaking disk at times when no signals are being transmitted.

13. A signal system embracing a loop-circuit, a central-station mechanism embracing a main battery and means by which the opposite poles of the main battery may be connected with the terminals of the loop-circuit, or one pole of the battery may be connected with the ground and the other with both terminals of the loop-circuit, and a signal-transmitting device in the loop-circuit comprising rotative circuit-breaking and circuit-closing disks which are electrically insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet the armature of which is connected with said arm and the coils of which are electrically connected with the loop-circuit and with said contact-arm, said armature being adapted, when the magnets are energized to hold the contact-arm in position to coact with the circuit-breaking disk and when the magnet is inactive and the armature retracted to hold the contact-arm in position to coact with the circuit-closing disk, a motor for actuating said circuit closing and breaking disks, a locking device operated by the motor for holding said arm in either one of its two positions during the turning of the disks and a switch operated by said locking device, one member of which is connected with the magnet-coils and which is closed when the locking device is in its disengaged position and, when closed, serves to divert the loop-circuit from said contact-arm and circuit-breaking disk.

' l4. Asignal transmitting device embracing rotative circuit-breaking and circuit-closing disks which are electrically insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet the armature of which is connected with said arm, said armature being adapted when the magnet is energized to hold the contact-arm in position to coact with the circuit-breaking disk, and when the magnet is inactive and the armature retracted to hold the contact-arm in position to coact with the circuit-closing disk, a conductor affording connection between said circuit-closing disk and the ground, a springactuated motor for turning said disks, and a locking device operated by the motor for holding said contact-arm in one or the other (it lits two positions during the turning of the c is ZS.

15. A signal-transmitting device embracing rotative circuit breaking and closing disks, which are electrically insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet, the

armature of which is connected with and opcrates said contact-arm, and the coils of which are connected with the signaling-circuit at one side of the transmitting device and with the contact-arm, said armature being adapted when the magnet is energized to hold the contact-arm in position to coact with the circuitbreaking disk and when the magnet is inactive and the armature retracted to hold the contact-arm in position to coact with the circuitclosing disk, a switch operated by the movement of said armature which is closed when the armature is retracted and at that time serves to connect the said contact-arm with the signaling-circuit at the other side of said transmitting device, and a conductor establishing electric connection between the circuitclosing disk and the ground.

16. A signaling system embracing a normally closed loop-circuit, a central-station apparatus embracing a main battery which is normally in the loop-circuit, means by which the said battery may be connected at its opposite poles with the terminals of the loopcircuit, or by which one pole of the battery may be connected with the ground and the other with both terminals of the loop-circuit, and a signal-transmitting device in said loopcircuit, embracing rotative circuit breaking and closing disks which are electrically insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet the armature of which is connected with and operates said contact-arm, and the coils of-which are in electric connection with said contact-arm and with the loop-circuit at one side of the signal-transmitting device, a conductor connect-ingsaid circuit-closing disk with the ground, and a switch operated by the movement of said armature and which is closed when the armature is in its retracted position, and at that time maintains electrical connection between the said contact-arm and the loop-circuit at the other side of the signal-transmitting device.

17. A signaling system embracing a normally closed loop-circuit, a central-station apparatus embracing a main battery and means by which the opposite poles of said battery may be connected with opposite terminals of said loop-circuit, or one pole of said battery may be connected with the ground and the other with both terminals of said loop-circuit, and a signal-transmitting device in said loopcircuit, embracing rotative circuit breaking and closing disks, which are electrically insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet the armature of which is connected with and moves said contact-arm, the coils of said magnet being connected with the contactarm and also with one side of the loop-circuit, a switch operated by the movement of said armature which is closed when the armature is retracted and which at that time serves to connect the said contact-arm with the other side of said loop-circuit, and a brush which acts on the circuit-closing disk and is connected by a conductor with the ground.

18. A signaling system embracing a normally closed loop-circuit, a central-station apparatus embracing a main battery and means by which the opposite poles of said battery may be connected with the opposite terminals of said loop-circuit, or one pole of said battery may be connected with the ground and the other with both terminals of said loop-circuit, and a signaltransmitting device in said loopcircuit, embracing rotative circuit breaking and closing disks, which are electrically insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet the armature of which is connected with and moves said contact-arm, the coils of said magnet being connected with the contactarm and also with one side of the loop-circuit, a switchoperated by the movement of said armature which is closed when the armature is retracted, and which at that time serves to connect the said contact-arm with the other side of said loop-circuit, a conductor establishing electric connection between the said circuit-closing disk and the ground, a springactuated motor for turning said disks and a locking device operated by the motor and adapted to hold the said contact-arm in either one of its two positions during the turning of the disks.

1-9. A signaling system embracing a normally closed loopcircuit, a central-station apparatus embracing a main battery and means by which the opposite poles of said battery may be connected with opposite teri'ninals of said loop-circuit, or one pole of said battery may be connected with the ground and the other with both terminals of said loop-circuit, and a sigmihtransmittingdevice in said loopcircuit embracing rotative circuit breaking and closing disks, which are electrically insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet the armature of which .is connected with and moves said contact-arm, the coils of said magnet being-connected with the contactarm and also with one side of said loop-cir-- cuit, a switch operated by said armature, which is closed when thearmature is retracted and which at that time serves to connect the said contact-arm with the other side of said loop-circuit, a conductor establishing electric connection between the said circuit-closing disk and the ground, a spring-actuated motor for turning said disks, a locking device operated by the motor and adapted to hold the said contact-arm in either one of the two positions during the turning of the disks, and a switch operated by the said locking device which is closed when said locking device is in its disengaged position, and which. when closed, serves to divert the loop-circuit from the contact-arm and circuit-breaking disk.

20. A signall-transmittingdevice embracing rotative circuit breaking and closing disks which are electrically insulated from each other, a contact-arm adapted to coact with either of said disks, an electromagnet to the armature of which said contact-arm is attached and by which it is moved, said armature being adapted when the magnet is energized to hold the contact-arm in position to coact with the circuit-ln'eaking disk, and when the magnet is inactive and the armature re tracted to hold the contact-arm in position to coact with the circuit-closing disk, a spring contact-piece on said contact-arm and a stationary contact-piece which together constitute a switch by which the contact-arm is connected with one side of the sigmding-circuit when the armature is retracted, and a brush in contact with said circuit-closing disk and which is connected with the ground.

21. A signal-transniittingdevice embracing a rotative circuit breaking and closing disk which are electrically insulated from each other, said circuit-breaking disk being connected with one side of the signaling-circuit, an electromagnet the coils of which are connected with the other side of said signalingcircnit, a contact-armwhich is attached to the armature of said electromagnet and which is adapted, when the electromagnet is energized, to coact with the circuitbrcaking disk, and when the magnet is inactive and the armature retracted to coact with the circuit-closing disk, said contact-arm being electrically connected with the coils of said clectronnignct, a locking device for holding the said armature and contact-arm in either of their two positions, said locking device embracing a pivoted locking-sector, and a holding-arm on the armature and a contact-piece adapted for contact with an arm carried by said sector, when said sector is in its disengaged position, such contact-piece and the arm of the sector being in electric connection with the magnet-coils and the loop circuit and constituting a switch, which, when closed, diverts the loop-circuit from the said contact-arm and circuit-breaking disk.

In testimony that I claim the foregoing as my invention 1 allix my signature, in presence of two witnesses, this 25th day of November, A. 1). 1903.

PAUL H. SCI'IMITT.

\Vitnesses:

C. CLARENFIQ Poona, (.iElt'lllUDlG J. Baron. 

